WP4430 Ground Based System

Abstract

The requirements of a possible HF ground based radar system as required for a continuous observation over a large ocean area is investigated. In these studies the basic geophysical tsunami parameters which are accessible for a HF radar remote sensing system are summarised and discussed. Here, the interaction of a High Frequency field HF (3–30 MHz) with ocean waves is of particular interest and therefore reviewed in details. An approaching Tsunami determines a relevant departure from standard ocean surface current patterns. By continuously monitoring the current field with a HF radar ground based system along the coastline, a potentially dangerous Tsunami could be accurately detected when the first wave front is still sufficiently far from the shore. The Doppler resolution for Tsunami induced surface currents is investigated by the Fourier transformed of two synthetic generated HF time series, backscattered from an illuminated ocean surface patch. The temporal evolution of the ocean surface is performed by a phase modulation in the Fourier domain.